Multigroup one-dimensional calculations were done recently to obtain estimates of critical masses, powerdensity distributions, and fissioning spectra for some homogeneous molten salt reactors having outer reflectors and central islands, which are to be placed inside the cur rently proposed MSRE vessel. For a 5-in.-thick outer reflector and a 1-ft-diameter island, both of which are beryllium, the calculated critical mass is 108 kg; 40% of the fissions occur at thermal, and the maximum power density of 3.9 times the core mean power density occurs at the island-salt interface. If the reflector thickness is increased to lO in., the critical mass is reduced to 34 kg; 67% of the fissions occur at thermal, and the peak power density of twice the core mean again occurs at the core island-salt interface. (auth)